Study Finds Connection Between Lead Poisoning, Breast Milk

A Harvard neuroscience professor has found that children of the indigenous population of the central Andes have been exposed to dangerously high levels of lead and mercury through the breast milk of their mothers.

After publishing the results of his study in July, S. Allen Counter, Jr., a clinical professor of neurology at the Medical School and Director of the Harvard Foundation, has led efforts to mitigate lead poisoning through education.

“I would go into villages and the children would come out to see me,” Counter said. “As they would greet me, these beautiful little children would smile and they had black stains in their teeth.”

S. Allen Counter, current director of The Harvard Foundation stands with members of an indigenous Ecuadorean community. Counter surveyed levels of lead found in the blood of community members and found that lead in breast milk was being transmitted to children.

Counter assembled a team of doctors and nurses from the U.S. and Ecuador to conduct the study, which found that most of the children and the adults in many Ecuadorian Andean villages, all at elevations of around 12,000 feet or higher, had lead poisoning as well as high levels of mercury in their blood.

According to Counter, the exposure to these toxic metals originates from the villagers’ livelihoods. Most of the young women earn their income by digging lead out of old car batteries. The metal can then be ground up and used to glaze ceramics, such as roof tiles, that can be sold to make a living.

“We look at some of the lead isotopes and by examining the types of lead, we can match the lead in the soil, in the food, in the battery, and in the children’s blood as all being the same lead,” Counter said. “We know it all came from the same source.”

To remedy this issue, Counter has launched the Lead Education Prevention Program, which educates local residents about the dangers of lead batteries and suggests alternative livelihoods for the villagers. Simultaneously, he has been raising funds for medicine that can significantly lower lead levels in the blood.

The study found a clear correlation with the levels of lead in Quechua mothers’ blood, their breast-milk, and the infants’ blood level. In many cases, these levels in children are extraordinarily high considering their limited exposure.

“It was unbelievable,” Counter said of the levels of lead detected in the children’s blood samples. He found over 100 micrograms of lead per deciliter of blood in some cases, while the U.S. Centers for Disease Control and Prevention places a person at risk if levels reach even 5 micrograms per deciliter.

Counter found that these elevated lead levels have serious neurocognitive effects.

“We followed some of the children over the years, and sadly we’ve seen evidence of a serious correlation, as we had predicted, between the level of lead exposure and an intellectual deficit and cognitive decline,” he said.

Most recently, he and other villagers met with Ecuador’s Minister of Health, who has approved the construction of a day care center in the most contaminated village. This way, mothers can drop off their children while they work to prevent any further exposure.

“I really am concerned,” Counter said. “I want to see these communities brought to good health.”